Space Future has been on something of a hiatus of late. With the concept of Space Tourism steadily increasing in acceptance, and the advances of commercial space, much of our purpose could be said to be achieved. But this industry is still nascent, and there's much to do. So...watch this space.

The main problem about space is how much it costs to get there: it's too expensive! And that's mainly because launch vehicles are expendable - either entirely, like satellite launchers, or partly, like the space shuttle.

So we need reusable launch vehicles. The trouble is that these will not only reduce the cost of launch - they'll also put the makers out of business, unless there's more to launch than just a few satellites a year, as there are today.

Fortunately there's a market that will generate far more launch business than satellites ever well - passenger travel. Market Research has shown that the idea of space tourism is very very popular. And so, just like aviation, the launch industry is going to find that most of its business will be carrying passengers.

But this idea of Space Tourism isn't at all familiar to most people, including the space industry, who are used to the idea that space is for research or military activities. Few people are aware of how much work has been done to show that tourism is a realistic goal, and how rapidly this work is now progressing.

Once travel to orbit becomes a commercial service, the question of how to get to space will be mainly one of saving up for a ticket - or looking for work in one of the many space hotels that will be built. Space offers unique pleasures including the view, and zero gravity activities that provide a whole range of things to do on an orbital holiday - including space sports.

Importantly, and contrary to what many people assume, the space agencies are not at all interested in space tourism, and are not trying to bring it about. This is a pity because space activities will never be profitable until tourism services begin, remaining small-scale, expensive, and dependent on taxes which come from you - which would you prefer?

Space is just another place where humans are going to live. And because space is almost limitless humans are going to live there in vast numbers in the future - in other words, it will become a whole new habitat.

Today most activities in space are government ones because getting to and from space is so expensive. Once travel to and from orbit is cheap enough, as on Earth, most activities in space will be carried out by individuals, private companies and organizations. At that time space activities will involve almost every industry - not just the aerospace industry but construction and interior design, catering and drinks, fashion and music, sports and entertainment, advertising and law, to name just a few.

Obviously, if people are going to live in space, they are going to need somewhere to live. Hotels are all very well for tourists, but workers will have more practical needs for their permanent accommodation - being close to work for one.

Living in space for long periods of time, or even permanently, is far more serious a prospect than merely staying for a few days or weeks. Much research in space today concerns the effect on the body of living in weightlessness or "zero gravity" for long periods. While this isn't a concern for tourists (we already know that living in zero G for a few weeks has no harmful effects) the long-term effects of low gravity have both benefits and drawbacks to health.

For many many people space tourism and even colonisation are attractive ideas. But in order for these to start we need vehicles that will take us to orbit and bring us back.

Current space vehicles clearly cannot. Only the Space Shuttle survives past one use, and that's only if you ignore the various parts that fall off (intentionally!) on the way up.

You could be forgiven for thinking that space is therefore an impossibly expensive place to get to. But this need not be the case. Launch to orbit requires accelerating to Mach 26, and so it uses a lot of propellant - about 10 tons per passenger. But there's no technical reason why reusable launch vehicles couldn't come to be operated routinely, just like aircraft. The only reason why this hasn't been done yet is that launch vehicle development has been left to government space agencies. And they have had neither the priority nor the will to achieve it - they don't use even 2% of their budgets (of $25 billion per year) to study the design of launch vehicles suitable for passenger service!

So it may well turn out to be private enterprise that is the solution - plenty of ideas for reusable launch vehicles exist, and with incentives like the X-Prize, there's going to be fierce competition to see who can be first.

Space Vehicles presents some of the ideas that could change the meaning of "Space" from being a remote place where government staff carry out "missions" to being a weekend destination, just a few minutes' flight away.

The space around Earth is filled with intense sunlight, undiffused by atmosphere, continuously. It represents an inexhausible supply of energy that can be converted to electricity using semiconductors - that is without the use of any moving parts.

A small fraction of this energy could supply a large part of the world's future energy requirements for the foreseeable future. In addition, it could do it without the need for any kind of fuel, and without producing any waste product.

All that's needed is large-area collectors - and that means large, thousands of square kilometers - and a way to transmit the collected power down to Earth. Several different methods are possible, but the one that has received the most effort so far is the use of microwave beams or wireless power transmission.